View Full Version : Solar panels
two fingers
22nd February 2011, 06:11 PM
Would post this in the renovators area but it's closed.
Do you have solar power that is connected to the grid. I've heard all the sales pitches about how it will transform my life, now I want the truth.
What's good about it won't keep me up at nights but what's bad about it will and I would prefer to get a good nights sleep. So if you have experiences that are of the negative kind I'd like to hear about them.
snowyskiesau
22nd February 2011, 06:32 PM
The renovators forum is still online, try here (http://www.renovateforum.com/f223/).
Bedford
22nd February 2011, 06:38 PM
Would post this in the renovators area but it's closed.
Nope, we're open for business. :)
malb
22nd February 2011, 08:22 PM
Issues to come to grips with;
The panels need to be predominately north facing, with an inclination approximately equal to your latitude for maximum efficiency.
The panels need to remain unshaded during the active sunlight period when you expect them to produce power. Each panel is formed from a large number of cells conected in a series/parallel fashion i.e there are a number of groups comprising cells connected in series to increase the output voltage, and the groups are connected in parallel to provide additional current. However shading 10% of a panel will reduce the panel output and array output to effectively zero as the shaded cells not only will not contribute power output, they will block the current flow from the unshaded cells they are in series with in the panel and the total current flow in the array. Therefore, the panels should not be located in areas partly or fully shaded by trees, structures, antennae/masts, chimneys etc.
The inverters used to convert DC (panels) to AC (mains) have a decent efficiency over a limited input voltage range. If the input voltage falls below that range the inverter does not produce significant mains energy. Conversely, as with all electronic components, they have a maximum input voltage rating and can be destroyed if that is exceeded. Hence the concerns about partial shading expressed above. It is essential that the overall system be carefully planned and designed to ensure that the panel output is within this safe/efficient range for the maximum period possible.
To be entitled to the bonuses etc applicable to solar grid connect, the system has to meet standards and be approved. Your electricity supplier will pay you for energy supplied to the grid, at a rate that may be about 3-4 times what they currently charge you for power, but there is a sting in the tail. To do this they will demand that you move into a new plan with a smart meter so they can meter your production. However they will charge more under the new plan, and may include time of day metering where they slug you heavily for peak demand usage. With normal aggregate metering, you might pay 18c/KWh for all consumption, with time of day metering, the base (off peak) rate is similar, but on a stinking hot day when everyone has aircons running and supply is barely keeping up with supply, or not, you might be getting stung $1.10/KWh. Your neighbour who is still on agregate metering would still be paying 18c/KWh, as the supplier reads the meter every month or two months and cannot tell if they used power during the peak times. Smart meter measure consumption in half hour blocks, making such schemes attractive to suppliers.
There is a lot of discussion on the Energy Matters forum about installation issues, compliance issues, etc. It would be worth checking this out if you are interested in going solar.
Hope this helps.
ian
22nd February 2011, 09:36 PM
One more thing to add to Malb's response ...
If your power retailer sends you a cheque for the power you generate -- the ATO have said they will treat the amount on the cheque as income which could affect your access to some Government benefits
If your power retailer provides you with a credit (or rebate) on your power bill -- the ATO say they will ignore the "income" for all purposes
graemet
24th February 2011, 09:24 PM
I've put in a 1.5Kw system, usual bill $900, first bill post install was $260.
kiwigeo
28th February 2011, 12:15 PM
If your power retailer provides you with a credit (or rebate) on your power bill -- the ATO say they will ignore the "income" for all purposes
Vultures...they'd tax air if they could. :~
Scribbly Gum
28th February 2011, 12:52 PM
Vultures...they'd tax air if they could. :~
Already been done.
In England during the Industrial Revolution there was a window tax. Yep - the result was no windows - to save money.
Effectively it was a tax on fresh air and light.
cheers
SG
I_wanna_Shed
28th February 2011, 01:23 PM
Already been done.
In England during the Industrial Revolution there was a window tax. Yep - the result was no windows - to save money.
Effectively it was a tax on fresh air and light.
cheers
SG
This is what brought about the term "daylight robbery". I was reading about it on Wikipedia a few months ago.
I chuckled when I read that (apparently) the more affluent types installed additional or fake windows, so they could show they could afford to pay more tax.
rotten_66
28th February 2011, 02:13 PM
One more thing to add to Malb's response ...
If your power retailer sends you a cheque for the power you generate -- the ATO have said they will treat the amount on the cheque as income which could affect your access to some Government benefits
If your power retailer provides you with a credit (or rebate) on your power bill -- the ATO say they will ignore the "income" for all purposes
If this is right then it opens up a whole can of tax worms. Surely I could then claim any costs associated with it such as the annual service/inspection of the system by an electrician (as required by the warranty), up grade of my meter box, depreciation of the system, maintenance/cleaning costs of the panels, the cost of any software/hardware to monitor, etc.
Why would they bother hassling me for a few hundred dollars worth of income and it is going to cost them many times that in further deductions????
Any incentive to put in a system that may actually do something to help the environment is therefore diminished.
Ron (I don't have a solar setup yet, but am, excuse the pun, currently looking at a 3.0kW system and if the budget can stretch a 4.5-5.0kW.)
damian
28th February 2011, 03:01 PM
malb put up an excellant post. I have only a couple of things to add:
When I go solar I'll be getting an "official" 1.5 kW system and collecting any rebates etc left at that time. I then intend to get some of the B grade cells available on ebay for about $1/watt and try building my own panels. I haven't used them and the process is labor intensive but the savings over pre made panels are enormous and thus I deem it worth a try.
graemet: Have you been switched to smart meters yet ? I know a number of people who saw the dramatic drop first bill only to go backwards after the smart meters were installed.
Also I thought NSW dropped the feed in tarriff to 20c a while back ?
I hope to look into a non tied system, and those relatively cheap batteries, something bromide as I recall, with a generator backup. I need to do some sums on my usage though.
rotten_66
28th February 2011, 10:16 PM
From my tax agent via the ATO.
Home solar system credits generated by returning power to the grid and taken as a cheque or e-transfer, ie Cashed in, are not considered income and therefore you are NOT taxed on it.
NOTE: If you are on a pension solar credits are considered as income for determining allowances, concessions and benefits. (Not sure if this is any credits or just those you "cash in".
Ron
graemet
28th February 2011, 10:26 PM
graemet: Have you been switched to smart meters yet ? I know a number of people who saw the dramatic drop first bill only to go backwards after the smart meters were installed.
Also I thought NSW dropped the feed in tarriff to 20c a while back ?
I got in before the feedin tarrif was lowered, so will have the 60c until 2014, and, no, we don't have a smart meter yet. No indication that one is coming, either.
artme
2nd March 2011, 02:10 PM
We had a system installed at the end of Sept. Over the last few days I have noted that the panel on the inverter has shown a red light(fault). It also shows a message reading "System Error".
The first time this happened was late in the evening so thought it might be to do with poor light.Next morning all was OK.Today the "System Error" message appeared in broad daylight. I rang the company and they said that this is the result of fluctations in the power grid and there was really nothing that could be done except to reset the system.
I did this but the "System Error" message re-appeared. I will ring them agin shortly because something else must be wrong.
HOWEVER Why would a system not be able to cope with these fluctuations??
If this keeps happening I will never get the full advantage of the system unless I sit beside the constantly monitor the state of affairs.:~:~
Rattrap
2nd March 2011, 04:01 PM
Artme, what brand is your inverter? I am just about to sign up for a solar install, i was going to go with a special the company was running using a Xantrax inverter (or similar spelling) however the salesman talked me away from that model inverter as it has issues when there is partial shading on the panels or something. Apparently it throws out error msgs that sound similar to what you have described. It might be totally unrelated to your problem but it did sound very similar to the description you have given.
rotten_66
2nd March 2011, 04:27 PM
From what I have read and seen the "best" inverters are SMA or Aurora, Xantrex and Latronics seem to be the next level down.
Aero-sharp though seems to be very hit and miss, on the Whirlpool and ATA (Alternative Technology Association) discussion sites I have read of people being on their 3rd one in about a year due to failures, so it is one brand that I am going to avoid,
Ron
ian
2nd March 2011, 08:45 PM
Artme
is your inverter exposed to the sun?
we were talking solar panels at work today and "apparently" if the inverter gets too hot it plays up.
I'm not sure what "too hot" means, but the colleague who has had his system since early last year has had to put a roof over the inverter to protect it from direct sun light
rotten_66
2nd March 2011, 10:20 PM
Inverters produce heat as they process the electricity that you generate from DC to AC, and they need to be able to exchange this heat to the surrounding air to cool. Direct sunlight adds extra heat and this can cause them to overheat and shut down for safety reasons. Some brands have big vanes to dissipate the heat, some a small fan to move air about check your own one to see what it has.
Try to avoid those with a cooling fan as it adds moving parts and uses power and one more thing to fail or wear out,
Ron
artme
6th March 2011, 12:18 AM
Ok Fellas, some answers. Sorry they are bit tardy in arriving but we have had no end of internet problems.
I believed I was getting a Xantrax inverter but I think it may be an Aero-sharp! Bummer!:C
Inverter is on the souther side of the house. No direct sun. Temp peading is always 32* or below.
No shade on panels.
Rang company again and they will send out a technician. Thing seem to be working rndomly ATM.
malb
6th March 2011, 06:33 PM
It would be usefull if there was a way to track through the hstory in the machine to get error codes for the fault.
Some possible causes of precautionary shutdown include,
Mains voltage out of inverter acceptable range (high or low), or supply disruptions
High mains harmonic/noise content ( ineffectively filtered inverters/SCR speed controllers in the neighbourhood)
High mains DC content (someone operating half wave rectified equipment/SCR speed controllers in neighbourhood)
Panel DC voltage below inverter tracking range
Panel Dc voltage above inverter maximum input voltage
Over temperature
To qualify for rebates etc the inverter used has to be on an approved devices list. The units on the list are capable of taking medium voltage DC power and converting it to mains power, but there is range of units and prices. One thing that distinguishes the high end units from the low end ones on the list is their capability for handling adverse conditions.
If you were told that you were getting Xantrex and you received something else without prior consultation, check what is listed in the initial purchase contract (not the installation manifest) and take action if you were not supplied the equipment you were supposed to.